package com.hmdp.utils;

import cn.hutool.core.lang.UUID;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import java.util.Collections;
import java.util.concurrent.TimeUnit;

/**
 * @author 靳
 * @version 1.0
 */

public class SimpleRedisLock implements ILock {

    private String name;
    private StringRedisTemplate stringRedisTemplate;
    private static final String key_prefix = "lock:";
    private static final String ID_prefix = UUID.randomUUID().toString(true) + "-";
    private static final DefaultRedisScript<Long> UNLOCK_SCRIPT;

    static {
        UNLOCK_SCRIPT = new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unlock.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }

    public SimpleRedisLock(String name, StringRedisTemplate stringRedisTemplate) {
        this.name = name;
        this.stringRedisTemplate = stringRedisTemplate;
    }

    @Override
    public boolean tryLock(long timeoutSec) {
        //获取线程标识
        String threadId = Thread.currentThread().getId() + ID_prefix;

        //获取锁
        Boolean success = stringRedisTemplate.opsForValue()
                .setIfAbsent(key_prefix + name, threadId, timeoutSec, TimeUnit.SECONDS);
        return Boolean.TRUE.equals(success);
    }

    @Override
    public void unlock() {
        //调用lua脚本
        stringRedisTemplate.execute(
                UNLOCK_SCRIPT,
                Collections.singletonList(key_prefix + name),
                ID_prefix + Thread.currentThread().getId());

    }



//    @Override
//    public void unlock() {
//        //获取线程标识
//        String threadId = ID_prefix + Thread.currentThread().getId();
//        //获取锁中的标识
//        String id = stringRedisTemplate.opsForValue().get(key_prefix + name);
//        //判断标识是否一致
//        if (threadId.equals(id)) {
//            //释放锁
//            stringRedisTemplate.delete(key_prefix + name);
//        }
//    }
}
